(meth)acrylate resin material, surface hardness enhancer, polycarbonate resin composition, and molded article

ABSTRACT

A (meth)acrylate resin material comprising a polymer (A1) having constituent units (a1) derived from a compound represented by formula (1) and constituent units (a2) derived from methyl methacrylate, and an acid (B) and/or a nucleating agent (C). In the formula, Ar represents an aryl group, and the aromatic ring in Ar is directly bonded to the ester end in formula (1).

TECHNICAL FIELD

The present invention relates to a (meth)acrylate resin material, asurface hardness enhancer, a polycarbonate resin composition, and amolded article.

This application is based upon and claims the benefit of priority of theprior Japanese Patent Application No. 2014-177274, filed in the JapanesePatent Office on Sep. 1, 2014, the prior Japanese Patent Application No.2014-175471, filed in the Japanese Patent Office on Aug. 29, 2014, andthe prior Japanese Patent Application No. 2014-229713, filed in theJapanese Patent Office on Nov. 12, 2014, the entire contents of whichare incorporated herein by reference.

BACKGROUND ART

Molded articles of polycarbonate resins are widely used as members(housing and the like) of various kinds of devices (electrical devices,electronic devices, office automation devices, and the like), opticalrecording media, automobile parts, building members, and the like sincethey have an excellent mechanical strength and exhibit excellent heatresistance, electrical properties, dimensional stability, flameretardancy, transparency, and the like.

However, molded articles of polycarbonate resins have a deficientsurface hardness so as not to be used as automobile head lamps, variouskinds of sheets, and the like.

As a molded article which contains a polycarbonate resin and has anexcellent surface hardness, the following one is disclosed.

A molded article obtained by molding a polycarbonate resin compositioncontaining a surface hardness enhancer composed of a polymer (A) havinga constitutional unit (a1) derived from an aromatic (meth)acrylate and aconstitutional unit (a2) derived from methyl methacrylate and apolycarbonate resin (JP 2010-116501 A).

However, the compatibility between the polycarbonate resin and the(meth)acrylate polymer in the surface hardness enhancer is insufficientin the polycarbonate resin composition described in JP 2010-116501 A.Hence, molding defects such as whitening are often caused in the moldedarticle described in Patent Literature 1.

CITATION LIST Patent Literature

JP 2010-116501 A

DISCLOSURE OF INVENTION

The invention provides a (meth)acrylate resin material and a surfacehardness enhancer which exhibit favorable compatibility with apolycarbonate resin and, in the case of being blended with apolycarbonate resin, provide a polycarbonate resin composition capableof providing a molded article which has an excellent surface hardnesswhile maintaining the optical properties of the polycarbonate resin andsuppressed molding defects such as whitening; a polycarbonate resincomposition capable of providing a molded article which has an excellentsurface hardness, excellent optical properties, and suppressed moldingdefects such as whitening; and a molded article which contains apolycarbonate resin and has an excellent surface hardness, excellentoptical properties, and suppressed molding defects such as whitening.

The invention provides a method of manufacturing a molded article whichhas an excellent surface hardness, excellent optical properties, andsuppressed molding defects such as whitening.

The invention has the following aspects.

[1] A (meth)acrylate resin material including: a polymer (A1) having aconstitutional unit (a1) derived from a compound represented by thefollowing Formula (1) and a constitutional unit (a2) derived from methylmethacrylate and at least one or more between an acid (B) and anucleophilic agent (C).

Here, Ar is an aryl group, and an aromatic ring in Ar is directly bondedto an ester terminal in Formula (1).

[2] A (meth)acrylate resin material including:

a polymer (A2) having a constitutional unit (a1) derived from a compoundrepresented by the following Formula (1), a constitutional unit (a2)derived from methyl methacrylate, and at least one or more between aconstitutional unit (b1) derived from an acid (B) and a constitutionalunit (c1) derived from a nucleophilic agent (C).

Here, Ar is an aryl group, and an aromatic ring in Ar is directly bondedto an ester terminal in Formula (1).

[3] The (meth)acrylate resin material according to [2], furtherincluding at least one or more between an acid (B) and a nucleophilicagent (C).

[4] The (meth)acrylate resin material according to any one of [1] to[3], in which the constitutional unit (a1) is at least one or morebetween a constitutional unit derived from phenyl methacrylate and aconstitutional unit derived from 2-naphthyl methacrylate.

[5] The (meth)acrylate resin material according to any one of [1] to[4], in which a proportion of the constitutional unit (a1) is from 5 to50% by mass in 100% by mass of a sum of the constitutional unit (a1) andthe constitutional unit (a2).

[6] The (meth)acrylate resin material according to any one of [1] to[5], in which a proportion of the constitutional unit (a1) is from 5 to25% by mass in 100% by mass of a sum of the constitutional unit (a1) andthe constitutional unit (a2).

[7] The (meth)acrylate resin material according to any one of [1] to[6], in which a proportion of the constitutional unit (a2) is from 50 to95% by mass in 100% by mass of a sum of the constitutional unit (a1) andthe constitutional unit (a2).

[8] The (meth)acrylate resin material according to any one of [1] to[7], in which the acid (B) is a compound having a carboxyl group.

[9] The (meth)acrylate resin material according to any one of [1] to[8], in which the acid (B) is at least one or more between methacrylicacid and acrylic acid.

[10] The (meth)acrylate resin material according to any one of [1] or[4] to [9], in which a content of the acid (B) is from 0.02 to 10 partsby mass with respect to 100 parts by mass of a sum of the constitutionalunit (a1) and the constitutional unit (a2).

[11] The (meth)acrylate resin material according to any one of [2] to[9], in which a content of the constitutional unit (b1) or a totalcontent of the acid (B) and the constitutional unit (b1) in a case offurther including an acid (B) is from 0.02 to 10 parts by mass withrespect to 100 parts by mass of a sum of the constitutional unit (a1)and the constitutional unit (a2).

[12] The (meth)acrylate resin material according to any one of [1] to[11], in which the nucleophilic agent (C) is a compound having ahydroxyl group.

[13] The (meth)acrylate resin material according to any one of [1] to[12], in which the nucleophilic agent (C) is a compound having astructure represented by the following Formula (2) in a molecule.

[14] The (meth)acrylate resin material according to any one of [1] to[13], in which the nucleophilic agent (C) is a compound having achemical structure to react with a polycarbonate resin in a molecule.

[15] The (meth)acrylate resin material according to any one of [1], [4]to [10], or [12] to [14], in which a content of the nucleophilic agent(C) is from 0.001 to 10 parts by mass with respect to 100 parts by massof the polymer (A1).

[16] The (meth)acrylate resin material according to any one of [2] to[9] or [11] to [14], in which a content of the constitutional unit (c1)or a total content of the nucleophilic agent (C) and the constitutionalunit (c1) in a case of further including the nucleophilic agent (C) isfrom 0.001 to 10 parts by mass with respect to 100 parts by mass of thepolymer (A2).

[17] The (meth)acrylate resin material according to any one of [1] to[16], in which a mass average molecular weight of the polymer (A1) orthe polymer (A2) is from 5000 to 30000.

[18] A surface hardness enhancer including the (meth)acrylate resinmaterial according to any one of [1] to [17].

[19] A polycarbonate resin composition including:

a polycarbonate resin (D); and

the (meth)acrylate resin material according to any one of [1] to [17].

[20] A molded article obtained by molding the polycarbonate resincomposition according to [19].

[21] The surface hardness enhancer according to [18], in which a pencilhardness of a molded article that is obtained by molding a polycarbonateresin composition containing the surface hardness enhancer according to[18] at 25 parts by mass with respect to 100 parts by mass of apolycarbonate resin (D) having a viscosity average molecular weight of16000 or more and 25000 or less and has a thickness of 2 mm measured inconformity with JIS K 5600-5-4 is F or higher.

[22] The surface hardness enhancer according to [18], in which haze of amolded article that is obtained by molding a polycarbonate resincomposition containing the surface hardness enhancer according to [18]at 25 parts by mass with respect to 100 parts by mass of a polycarbonateresin (D) having a viscosity average molecular weight of 16000 or moreand 25000 or less and has a thickness of 2 mm measured in conformitywith JIS K 7136 is 0.5% or less.

[23] The surface hardness enhancer according to [18], in which haze of aregion of 16 mm×12 mm including a place at which whitening of a moldedarticle is caused in the molded article that is obtained by molding apolycarbonate resin composition containing the surface hardness enhanceraccording to [18] at 25 parts by mass with respect to 100 parts by massof a polycarbonate resin (D) having a viscosity average molecular weightof 16000 or more and 25000 or less and has a shape 1A described in JISK7162 is 25% or less.

[24] A method of manufacturing a polycarbonate resin composition, inwhich a polycarbonate resin (D) is further blended at from 1 to 400parts by mass with respect to 100 parts by mass of the polycarbonateresin composition according to [19].

[25] A polycarbonate resin composition having a peak at least at one ormore retention times between 19.3 minutes and 22.1 minutes in a massspectrum obtained when 5 μL of a 20% methanol solution oftetramethylammonium hydroxide (TMAH) is added to 200 μg of thepolycarbonate resin composition, the polycarbonate resin composition andTMAH are thermally decomposed through a reaction by a thermaldecomposition apparatus set at 400° C., and a gas thus generated isseparated.

[26] The polycarbonate resin composition according to [25], including apolymer having a constitutional unit derived from at least one or morebetween chemical structures represented by the following Formula (3) andthe following Formula (4).

The (meth)acrylate resin material of the invention exhibits favorablecompatibility with a polycarbonate resin. In addition, a polycarbonateresin composition capable of providing a molded article which has anexcellent surface hardness while maintaining the optical properties ofthe polycarbonate resin and suppressed molding defects such as whiteningis obtained in the case of blending the (meth)acrylate resin material ofthe invention with a polycarbonate resin.

The surface hardness enhancer of the invention exhibits favorablecompatibility with a polycarbonate resin. In addition, a polycarbonateresin composition capable of providing a molded article which has anexcellent surface hardness while maintaining the optical properties ofthe polycarbonate resin and suppressed molding defects such as whiteningis obtained in the case of blending the surface hardness enhancer of theinvention with a polycarbonate resin.

According to the polycarbonate resin composition of the invention, it ispossible to obtain a molded article having an excellent surfacehardness, excellent optical properties, and suppressed molding defectssuch as whitening.

The molded article of the invention is a molded article which contains apolycarbonate resin and has an excellent surface hardness, excellentoptical properties, and suppressed molding defects such as whitening.

By the manufacturing method of the invention, it is possible to obtain amolded article having an excellent surface hardness, excellent opticalproperties, and suppressed molding defects such as whitening.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram which illustrates the measurement results forthermal decomposition of a polycarbonate resin composition obtained inExample 15;

FIG. 2 is a diagram which illustrates the results for mass spectrometricanalysis of a sample having a peak at a retention time of 19.3 minutesin the mass spectrum of a polycarbonate resin composition obtained inExample 15; and

FIG. 3 is a diagram which illustrates the results for mass spectrometricanalysis of a sample having a peak at a retention time of 22.1 minutesin the mass spectrum of a polycarbonate resin composition obtained inExample 15.

BEST MODE FOR CARRYING OUT THE INVENTION

The definitions of the following terms apply throughout the presentspecification and the claims.

The term “constitutional unit” means a constitutional unit derived froma monomer in a polymer formed through polymerization of the monomer or aconstitutional unit in which a part of the constitutional unit isconverted into another structure through treatment of the polymer.

The term “mass average molecular weight” is a mass average molecularweight in terms of polystyrene measured by gel permeation chromatography(GPC) at a column temperature of 40° C. using tetrahydrofuran as aneluent.

The term “(meth)acrylate” is a generic name for an acrylate and amethacrylate.

<(Meth)acrylate Resin Material>

The (meth)acrylate resin material of the invention is the following(meth)acrylate resin material (α) or (meth)acrylate resin material (β).The difference between the (meth)acrylate resin material (α) and the(meth)acrylate resin material (β) is that at least one or more betweenan acid (B) and a nucleophilic agent (C) is contained as one componentof the (meth)acrylate resin material or at least one or more between anacid (B) and a nucleophilic agent (C) is incorporated in the(meth)acrylate polymer as a constitutional unit of the polymer.

(α) a (meth)acrylate resin material containing a polymer (A1) having aconstitutional unit (a1) derived from a compound represented by thefollowing Formula (1) and a constitutional unit (a2) derived from methylmethacrylate and at least one or more between an acid (B) and anucleophilic agent (C).

(β) a (meth)acrylate resin material containing a polymer (A2) having aconstitutional unit (a1) derived from a compound represented by thefollowing Formula (1), a constitutional unit (a2) derived from methylmethacrylate, and at least one or more between a constitutional unit(b1) derived from an acid (B) and a constitutional unit (c1) derivedfrom a nucleophilic agent (C).

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

Incidentally, the (meth)acrylate resin material (β) may contain at leastone or more between the acid (B) and the nucleophilic agent (C) as onecomponent in addition to the polymer (A2).

(Polymer (A1))

The polymer (A1) has the constitutional unit (a1) and the constitutionalunit (a2). The polymer (A1) may have a constitutional unit (a3) derivedfrom another monomer if necessary. The polymer (A1) does not have theconstitutional unit (b1) derived from the acid (B) and theconstitutional unit (c1) derived from the nucleophilic agent (C).

The mass average molecular weight of the polymer (A1) is preferably from5,000 to 30,000, more preferably from 10,000 to 20,000, and still morepreferably from 10,000 to 15,000. The molded article has a superiorsurface hardness when the mass average molecular weight of the polymer(A1) is 5000 or more. The molding defects of the molded article arefurther suppressed when the mass average molecular weight of the polymer(A1) is 30,000 or less.

Examples of the method of manufacturing the polymer (A1) may include asuspension polymerization method, a solution polymerization method, anemulsion polymerization method, and a bulk polymerization method whichare known. As the method of manufacturing the polymer (A1), a suspensionpolymerization method or an emulsion polymerization method is preferablefrom the viewpoint of easy recovery of the polymer (A1).

(Polymer (A2))

The polymer (A2) has the constitutional unit (a1), the constitutionalunit (a2), and at least one or more between the constitutional unit (b1)and the constitutional unit (c1). The polymer (A2) may have aconstitutional unit (a3) derived from another monomer if necessary.

The mass average molecular weight of the polymer (A2) is preferably from5,000 to 30,000, more preferably from 10,000 to 20,000, and still morepreferably from 10,000 to 15,000. The molded article has a superiorsurface hardness when the mass average molecular weight of the polymer(A2) is 5000 or more. The molding defects of the molded article arefurther suppressed when the mass average molecular weight of the polymer(A2) is 30,000 or less.

Examples of the method of manufacturing the polymer (A2) may include asuspension polymerization method, a solution polymerization method, anemulsion polymerization method, and a bulk polymerization method whichare known. As the method of manufacturing the polymer (A2), a suspensionpolymerization method or an emulsion polymerization method is preferablefrom the viewpoint of easy recovery of the polymer (A2).

(Constitutional Unit (a1))

The constitutional unit (a1) is a constitutional unit derived from acompound represented by the following Formula (1). The constitutionalunit (a1) improves the optical properties (transparency and the like) ofthe molded article.

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

Examples of the compound represented by Formula (1) may include phenylmethacrylate, o-diphenyl methacrylate, p-diphenyl methacrylate,o-chlorophenyl methacrylate, 1-naphthyl methacrylate, 2-naphthylmethacrylate, 4-methoxyphenyl methacrylate, 4-chlorophenyl methacrylate,2,4,6-trichlorophenyl methacrylate, and 4-tert-butylphenyl methacrylate.The constitutional unit (a1) may be used singly or two or more kindsthereof may be used concurrently.

As the constitutional unit (a1), at least one or more between aconstitutional unit derived from phenyl methacrylate and aconstitutional unit derived from 2-naphthyl methacrylate are preferablefrom the viewpoint of excellent heat resistance of the molded article.

The proportion of the constitutional unit (a1) is preferably from 5 to50% by mass, more preferably from 10 to 40% by mass, and still morepreferably from 15 to 30% by mass in 100% by mass of the sum of theconstitutional unit (a1) and the constitutional unit (a2). In addition,the proportion of the constitutional unit (a1) is preferably from 5 to30% by mass and more preferably from 5 to 25% by mass in 100% by mass ofthe sum of the constitutional unit (a1) and the constitutional unit (a2)as another aspect of the invention. The molded article exhibits superioroptical properties such as transparency when the constitutional unit(a1) is 5% by mass or more. The molded article has a superior surfacehardness when the constitutional unit (a1) is 50% by mass or less.

Incidentally, the proportion and content of the constitutional unit inthe polymer can be calculated from, for example, the mass of the monomerused in manufacture of the polymer.

(Constitutional Unit (a2))

The constitutional unit (a2) is a constitutional unit derived frommethyl methacrylate. The constitutional unit (a2) improves the surfacehardness of the molded article.

The proportion of the constitutional unit (a2) is preferably from 50 to95% by mass, more preferably from 60 to 90% by mass, and still morepreferably from 70 to 85% by mass in 100% by mass of the sum of theconstitutional unit (a1) and the constitutional unit (a2). In addition,the proportion of the constitutional unit (a2) is preferably from 70 to95% by mass and more preferably from 75 to 95% by mass in 100% by massof the sum of the constitutional unit (a1) and the constitutional unit(a2) as another aspect of the invention. The molded article has asuperior surface hardness when the constitutional unit (a2) is 50% bymass or more. The molded article exhibits superior optical properties(transparency and the like) when the constitutional unit (a2) is 95% bymass or less.

(Constitutional Unit (a3))

The constitutional unit (a3) is a constitutional unit derived from amonomer other than the monomer having a chemical structure representedby Formula (1), methyl methacrylate, the acid (B), and the nucleophilicagent (C).

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

Examples of the monomer constituting the constitutional unit (a3) mayinclude the following ones.

Methacrylate: ethyl methacrylate, butyl methacrylate, propylmethacrylate, 2-ethylhexyl methacrylate, and the like (provided that themonomer having a chemical structure represented by Formula (1) andmethyl methacrylate are excluded).

Acrylate: methyl acrylate, ethyl acrylate, butyl acrylate, propylacrylate, 2-ethylhexyl acrylate, glycidyl acrylate, phenyl acrylate,1-naphthyl acrylate, 2-naphthyl acryl ate, p-diphenyl acryl ate,o-diphenyl acryl ate, o-chlorophenyl acryl ate, 4-methoxyphenylacrylate, 4-chlorophenyl acrylate, 2,4,6-trichlorophenyl acrylate,4-tert-butylphenyl acrylate, and the like.

Vinyl cyanide monomer: acrylonitrile, methacrylonitrile, and the like.

Diene-based monomer: butadiene, isoprene, dimethylbutadiene, and thelike.

Vinyl ether-based monomer: vinyl methyl ether, vinyl ethyl ether, andthe like.

Carboxylic acid-based vinyl monomer: vinyl acetate, vinyl butyrate, andthe like.

Olefin-based monomer: ethylene, propylene, isobutylene, and the like.

Vinyl halide-based monomer: vinyl chloride, vinylidene chloride, and thelike.

Maleimide-based monomer: maleimide, N-phenylmaleimide,N-cyclohexylmaleimide, N-methylmaleimide, and the like.

Crosslinking agent: allyl (meth)acrylate, divinylbenzene, 1,3-butylenedimethacrylate, and the like.

As another monomer, a methacrylate, an acrylate, and a vinyl cyanidemonomer are preferable from the viewpoint of excellentcopolymerizability, namely, reactivity in copolymerization, and anacrylate is more preferable from the viewpoint of suppressing thermaldecomposition of the polymer (A1) and polymer (A2).

Another monomer may be used singly or two or more kinds thereof may beused concurrently.

The content of the constitutional unit (a3) is preferably from 0 to 10parts by mass with respect to 100 parts by mass of the sum of theconstitutional unit (a1) and the constitutional unit (a2). The moldedarticle exhibits excellent thermal decomposition resistance when thecontent of the constitutional unit (a3) is 10 parts by mass or less.

(Acid (B))

The acid (B) is a component contained in the (meth)acrylate resinmaterial of the invention. The acid (B) is contained as one component ofthe (meth)acrylate resin material in the (meth)acrylate resin material(α), and it is contained as the constitutional unit ( )) of the polymer(A2) in the (meth)acrylate resin material (β).

The acid (B) improves the compatibility between a polycarbonate resinand the (meth)acrylate resin material or the surface hardness enhancer.

(B) is not particularly limited as long as it is a compound capable ofgenerating a proton, namely, a Broensted acid. Examples of the acid (B)may include methacrylic acid, acrylic acid, anhydrous methacrylic acid,anhydrous acrylic acid, maleic acid, anhydrous maleic acid, itaconicacid, stearic acid, acetic acid, citric acid, formic acid, lactic acid,oxalic acid, tartaric acid, ascorbic acid, Meldrum's acid, hydrochloricacid, sulfuric acid, fuming sulfuric acid, phosphoric acid,fluorosulfonic acid, nitric acid, chromic acid, boric acid, andbenzenesulfonic acid. As (B), a compound having a carboxyl group ispreferable from the viewpoint of excellent heat resistance of the moldedarticle, and at least one or more between methacrylic acid and acrylicacid are more preferable from the viewpoint of excellentcopolymerizability.

The content of the acid (β) in the (meth)acrylate resin material (α) ispreferably from 0.001 to 10 parts by mass, more preferably from 001 to 5parts by mass, and still more preferably from 0.001 to 2 parts by masswith respect to 100 parts by mass of the sum of the constitutional unit(a1) and the constitutional unit (a2). In addition, the content of theacid (B) in the (meth)acrylate resin material (α) is preferably from0.02 to 10 parts by mass, more preferably from 0.02 to 5 parts by mass,and still more preferably from 0.02 to 2 parts by mass with respect to100 parts by mass of the sum of the constitutional unit (a1) and theconstitutional unit (a2) as another aspect of the invention. The moldingdefects of the molded article are further suppressed when the content ofthe acid (B) in the (meth)acrylate resin material (α) is 0.001 part bymass or more. The polycarbonate resin composition exhibits excellentmoldability when the content of the acid (B) in the (meth)acrylate resinmaterial (α) is 10 parts by mass or less.

(Constitutional Unit (b1))

The constitutional unit (1)1) is a constitutional unit derived from theacid (B).

As the acid (B) constituting the constitutional unit (b1), an acid (B1)copolymerizable with a monomer having a chemical structure representedby Formula (1), methyl methacrylate, or another monomer is preferableamong the acids (B) from the viewpoint of being easily introduced as aconstitutional unit.

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

Examples of the acid (B1) constituting the constitutional unit (b1) mayinclude methacrylic acid, acrylic acid, anhydrous methacrylic acid,anhydrous acrylic acid, maleic acid, anhydrous maleic acid, and itaconicacid.

The content of the constitutional unit (b1) in the (meth)acrylate resinmaterial (β) or the total content of the acid (B) and the constitutionalunit (b1) in the case of further containing the acid (B) is preferablyfrom 0.001 to 10 parts by mass, more preferably from 0.001 to 5 parts bymass, and still more preferably from 0.001 to 2 parts by mass withrespect to 100 parts by mass of the sum of the constitutional unit (a1)and the constitutional unit (a2). In addition, the content of theconstitutional unit (b1) in the (meth)acrylate resin material (β) or thetotal content of the acid (B) and the constitutional unit (b1) in thecase of further containing the acid (B) is preferably from 0.02 to 10parts by mass, more preferably from 0.02 to 5 parts by mass, and stillmore preferably from 0.02 to 2 parts by mass with respect to 100 partsby mass of the sum of the constitutional unit (a1) and theconstitutional unit (a2) as another aspect of the invention. The moldingdefects of the molded article are further suppressed when the content ofthe constitutional unit (b1) in the (meth)acrylate resin material (β) orthe total content of the acid (B) and the constitutional unit (b1) inthe case of further containing the acid (B) is 0.001 part by mass ormore. The polycarbonate resin composition exhibits excellent moldabilitywhen the content of the constitutional unit (b1) in the (meth)acrylateresin material (β) or the total content of the acid (B) and theconstitutional unit (b1) in the case of further containing the acid (B)is 10 parts by mass or less.

The (meth)acrylate resin material of the invention described aboveexhibits favorable compatibility with a polycarbonate resin since itcontains the acid (B) or the (meth)acrylate polymer has theconstitutional unit (b1) derived from the acid (B). Consequently, apolycarbonate resin composition capable of providing a molded articlehaving suppressed molding defects is obtained in the case of blendingthe (meth)acrylate resin material of the invention with a polycarbonateresin.

In addition, in the (meth)acrylate resin material of the invention, the(meth)acrylate polymer has the constitutional unit (a2) derived frommethyl methacrylate, and it is thus possible to obtain a molded articlehaving an excellent surface hardness in the case of blending the(meth)acrylate resin material of the invention with a polycarbonateresin.

In addition, in the (meth)acrylate resin material of the invention, the(meth)acrylate polymer has the constitutional unit (a1) derived from acompound represented by Formula (1), and a polycarbonate resincomposition capable of providing a molded article exhibiting excellentoptical properties, namely, transparency is thus obtained in the case ofblending the (meth)acrylate resin material of the invention with apolycarbonate resin.

(Nucleophilic Agent (C))

The nucleophilic agent (C) is a component contained in the(meth)acrylate resin composition of the invention. The nucleophilicagent (C) improves the compatibility between a polycarbonate resin andthe (meth)acrylate resin material and the surface hardness enhancer.

The nucleophilic agent (C) is not particularly limited as long as it isa compound exhibiting nucleophilicity. Examples of the nucleophilicagent (C) may include a compound having a hydroxyl group, an amine, anorganophosphorus compound, and a compound having a chemical structurewhich reacts with a polycarbonate resin in the molecule.

Examples of the compound having a hydroxyl group may include methanol,ethanol, isopropanol, ethylene glycol, glycerin, lauryl alcohol, stearylalcohol, bisphenol A, bisphenol AP, bisphenol B, bisphenol BP, bisphenolC, bisphenol E, bisphenol F, bisphenol G, bisphenol M, bisphenol S,bisphenol P, hydroxyethyl acrylate, hydroxyethyl methacrylate,hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutylmethacrylate, and hydroxybutyl acrylate.

Examples of the amine may include ammonia, trimethylamine, aniline,dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate,diethylaminoethyl methacrylate, diethylaminoethyl acrylate,tert-butylaminoethyl methacrylate, and tert-butylaminoethyl acrylate.

Examples of the organophosphorus compound may include phosphine,triphenylphosphine, trimethylphosphine, triethylphosphine,2-phosphonooxyethyl methacrylate, and 2-phosphonooxyethyl acrylate.

Examples of the compound having a chemical structure which reacts with apolycarbonate resin in the molecule may include acetolactone,propiolactone, butyrolactone, valerolactone, and a (meth)acrylate havinga chemical structure represented by the following Formula (5).

In Formula (5), n=1 to 20, and m=1 to 20.

It is preferable that n=1 to 10 and m=1 to 10 and it is more preferablethat n=1 to 5 and m=1 to 5 since it is possible to suppress moldingdefects of the molded article.

As the nucleophilic agent (C), it is preferable to use a compound havinga hydroxyl group from the viewpoint of obtaining a molded article whichexhibits excellent optical properties.

As the nucleophilic agent (C), a compound having a structure representedby the following Formula (2) in the molecule is preferable and acompound which has a structure represented by the following Formula (2)in the molecule and a hydroxyl group is still more preferable from theviewpoint of obtaining a molded article which exhibits excellent opticalproperties.

As the compound which has a structure represented by Formula (2) in themolecule and a hydroxyl group, those having a hydroxyaryl group arepreferable, and examples thereof may include bisphenol A, bisphenol C,and bisphenol P.

The content of the nucleophilic agent (C) in the (meth)acrylate resinmaterial (α) is preferably from 0.001 to 10 parts by mass, morepreferably from 0.001 to 5 parts by mass, and still more preferably from0.001 to 2 parts by mass with respect to 100 parts by mass of thepolymer (A1). The molding defects of the molded article are furthersuppressed when the content of the nucleophilic agent (C) is 0.001 partby mass or more. In addition, the molded article exhibits excellentthermal properties such as heat resistance when the content of thenucleophilic agent (C) is 10 parts by mass or less.

(Constitutional Unit (c1))

The constitutional unit (c1) is a constitutional unit derived from thenucleophilic agent (C). The constitutional unit (c1) improves thecompatibility between a polycarbonate resin and the (meth)acrylate resinmaterial and the surface hardness enhancer.

As the nucleophilic agent (C) constituting the constitutional unit (c1),a nucleophilic agent (C1) copolymerizable with a monomer having achemical structure represented by Formula (1), methyl methacrylate, oranother monomer is preferable among the nucleophilic agents (C) from theviewpoint of being easily introduced into the polymer (A2) as aconstitutional unit.

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

Examples of the nucleophilic agent (C1) may include a compound having ahydroxyl group, an amine, an organophosphorus compound, and a compoundhaving a chemical structure which reacts with a polycarbonate resin inthe molecule.

Examples of the compound having a hydroxyl group may includehydroxybutyl methacrylate, hydroxybutyl acrylate, hydroxyethylmethacrylate, and hydroxyethyl acrylate.

Examples of the amine may include dimethylaminoethyl methacrylate,dimethylaminoethyl acrylate, diethylaminoethyl methacrylate,diethylaminoethyl acrylate, tert-butylaminoethyl methacrylate, andtert-butylaminoethyl acrylate.

Examples of the organophosphorus compound may include2-phosphonooxyethyl methacrylate and 2-phosphonooxyethyl acrylate.

Examples of the compound having a chemical structure which reacts with apolycarbonate resin in the molecule may include a (meth)acrylate havinga chemical structure represented by the following Formula (5). Examplesof such a compound may include the “PLACCEL FA1”, “PLACCEL FA2”,“PLACCEL FA3”, “PLACCEL FA4”, “PLACCEL FA5”, “PLACCEL FM1 ”, “PLACCELFM2”, “PLACCEL FM3”, “PLACCEL FM4”, and “PLACCEL FM5” of trade namesmanufactured by DAICEL CORPORATION. These may be used singly or two ormore kinds thereof may be used concurrently. The “PLACCEL FM1”, “PLACCELFM2”, “PLACCEL FM3”, “PLACCEL FM4”, and “PLACCEL FM5” are preferablefrom the viewpoint of excellent heat resistance of the molded article.In addition, the proportion occupied by a chemical structure representedby the following Formula (5) in the total mass of the (meth)acrylate ispreferably from 0.0001 to 30% by mass.

In Formula (5), n=1 to 20 and m=1 to 20.

It is preferable that n=1 to 10 and m=1 to 10 and it is more preferablethat n=1 to 5 and m=1 to 5 since it is possible to suppress moldingdefects of the molded article.

As the nucleophilic agent (C1), a compound having a chemical structurewhich reacts with a polycarbonate resin in the molecule is preferablesince molding defects are suppressed.

The content of the constitutional unit (c1) in the (meth)acrylate resinmaterial (β) or the total content of the nucleophilic agent (C) and theconstitutional unit (c1) in the case of further containing thenucleophilic agent (C) is preferably from 0.001 to 10 parts by mass,more preferably from 0.001 to 5 parts by mass, and still more preferablyfrom 0.001 to 1 part by mass with respect to 100 parts by mass of thesum of the polymer (A2). The molding defects of the molded article arefurther suppressed when the content of the constitutional unit (c1) inthe (meth)acrylate resin material (β) or the total content of thenucleophilic agent (C) and the constitutional unit (c1) in the case offurther containing the nucleophilic agent (C) is 0.001 part by mass ormore. The molded article exhibits superior optical properties(transparency and the like) when the content of the constitutional unit(c1) in the (meth)acrylate resin material (β) or the total content ofthe nucleophilic agent (C) and the constitutional unit (c1) in the caseof further containing the nucleophilic agent (C) is 10 parts by mass orless.

The (meth)acrylate resin material of the invention described aboveexhibits favorable compatibility with a polycarbonate resin since itcontains the nucleophilic agent (C) or the (meth)acrylate polymer hasthe constitutional unit (c1) derived from the nucleophilic agent (C).Consequently, it is possible to obtain a molded article havingsuppressed molding defects by molding a composition in which the(meth)acrylate resin material of the invention is blended with apolycarbonate resin.

In addition, in the (meth)acrylate resin material of the invention, thepolymer (A1) or polymer (A2) has the constitutional unit (a2) derivedfrom methyl methacrylate, and it is thus possible to obtain a moldedarticle having an excellent surface hardness by molding a composition inwhich the (meth)acrylate resin material of the invention is blended witha polycarbonate resin.

In addition, in the (meth)acrylate resin material of the invention, thepolymer (A1) or polymer (A2) has the constitutional unit (a1) derivedfrom the following Formula (1), and it is thus possible to obtain amolded article exhibiting excellent optical properties, namely,transparency in the case of blending the (meth)acrylate resin materialof the invention with a polycarbonate resin.

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

<Surface Hardness Enhancer>

The (meth)acrylate resin material of the invention can be suitably usedas a surface hardness enhancer of a polycarbonate resin since it exertsthe effects described above.

Moreover, the surface hardness enhancer of the invention can exert thesame effects as those of the (meth)acrylate resin material of theinvention.

With regard to the surface hardness enhancer of the invention, it ispreferable that a pencil hardness of a molded article that is obtainedby blending the surface hardness enhancer at 25 parts by mass withrespect to 100 parts by mass of a polycarbonate resin (D) having aviscosity average molecular weight of from 16000 to 25000 and moldingthe mixture and has a thickness of 2 mm measured in conformity with JISK 5600-5-4 is F or higher.

With regard to the surface hardness enhancer of the invention, the hazeof a molded article that is obtained by blending the surface hardnessenhancer at 25 parts by mass with respect to 100 parts by mass of apolycarbonate resin (D) having a viscosity average molecular weight offrom 16000 to 25000 and molding the mixture and has a thickness of 2 mmmeasured in conformity with JIS K 7136 is preferably 0.5% or less, morepreferably 0.45% or less, and still more preferably 0.4% or less.

With regard to the surface hardness enhancer of the invention, the hazeof a region of 16 mm×12 mm including a place at which whitening of amolded article is caused in the molded article that is obtained byblending the surface hardness enhancer at 25 parts by mass with respectto 100 parts by mass of a polycarbonate resin (D) having a viscosityaverage molecular weight of from 16000 to 25000 and molding the mixtureat an injection temperature of 280° C., a mold temperature of 80° C.,and an injection pressure of 95 MPa by using a 100 t injection moldingmachine SE-100DU manufactured by Sumitomo Heavy Industries, Ltd. and hasthe shape 1A described in JIS K7162 is preferably 25% or less, morepreferably 20% or less, and still more preferably 17% or less.

<Polycarbonate Resin Composition>

The polycarbonate resin composition of the invention contains apolycarbonate resin (D) and the (meth)acrylate resin material of theinvention. The polycarbonate resin composition of the invention maycontain a component other than the polycarbonate resin (D) and the(meth)acrylate resin material of the invention if necessary.

(Polycarbonate Resin (D))

The polycarbonate resin (D) is not particularly limited as long as it isa polymer compound having a carbonic ester bond (—O—C(O)—O—) in the mainchain.

Examples of the polycarbonate resin (D) may include an aromaticpolycarbonate that is usually produced through a reaction between adihydric phenol and a carbonate precursor. Specific examples thereof mayinclude those produced by reacting a dihydric phenol with a carbonateprecursor by a solution method or a melting method, and more specificexamples thereof may include those produced by reacting a dihydricphenol with phosgene and those produced by reacting a dihydric phenolwith diphenyl carbonate or the like by a transesterification method.

Examples of the dihydric phenol may include2,2-bis(4-hydroxyphenyl)propane [bisphenol A],2,2-bis(3-methyl-4-hydroxyphenyl)propane [bisphenol C],bis(hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane,2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4,4′-dihydroxydiphenyl,bis(4-hydroxyphenyl)cycloalkane, bis(4-hydroxyphenyl) oxide,bis(4-hydroxyphenyl) sulfide, bis(4-hydroxyphenyl) sulfone,bis(4-hydroxyphenyl) sulfoxide, bis(4-hydroxyphenyl) ether,bis(4-hydroxyphenyl) ketone, and any halogen substituted productthereof. In addition to these, examples of the dihydric phenol mayinclude hydroquinone, resorcin, and catechol.

As the dihydric phenol, bis(hydroxyphenyl)alkane-based one is preferableand bisphenol A is particularly preferable from the viewpoint of cost.

The dihydric phenol may be used singly or two or more kinds thereof maybe used concurrently.

Examples of the carbonate precursor may include a carbonyl halide, acarbonyl ester, and a haloformate, and specific examples thereof mayinclude phosgene, a dihaloformate of a dihydric phenol, diphenylcarbonate, dimethyl carbonate, and diethyl carbonate.

The polycarbonate resin (D) may have a branched structure. Examples ofthe branching agent for introducing the branched structure into thepolycarbonate resin (D) may include 1,1,1-tris(4-hydroxyphenyl)ethane,α,α′,α″-tris(4-hydroxyphenyl)-1,3,5-triisopropylbenzene, phloroglucin,trimellitic acid, and isatin bis(o-cresol).

The polycarbonate resin (D) may be a copolymer having a polycarbonateportion and a polyorganosiloxane portion, or it may be a polycarbonateresin containing this copolymer. The polyorganosiloxane portion ispreferably from 1 to 40% by mass in the total mass of the polycarbonateresin (D) in a case in which the polycarbonate resin (D) contains thepolyorganosiloxane portion.

The polycarbonate resin (D) may be a polyester-polycarbonate resinobtained by reacting a dihydric phenol with a carbonate precursor in thepresence of an ester precursor, namely, a bifunctional carboxylic acidsuch as terephthalic acid, an ester forming derivative thereof, or thelike. The polyester portion is preferably from 1 to 50% by mass in thetotal mass of the polycarbonate resin (D) in a case in which thepolycarbonate resin (D) is a polyester-polycarbonate resin.

The polycarbonate resin (D) may be a mixture of various polycarbonateresins.

In the manufacture of the polycarbonate resin (D), phenol,p-t-butylphenol, p-t-octylphenol, p-cumylphenol, and the like may beused for adjustment of the molecular weight.

The viscosity average molecular weight of the polycarbonate resin (D)can be calculated by a viscosity method, and it is preferably from15,000 to 30,000, more preferably from 16,000 to 27,000, and still morepreferably from 17,000 to 25,000. The polycarbonate resin compositionexhibits excellent moldability and the molded article has an excellentsurface hardness when the viscosity average molecular weight is withinthe above range.

In the case of using phenol, p-t-butylphenol, p-t-octylphenol,p-cumylphenol, and the like for adjustment of the molecular weight, theproportion of these to the total mass of the polycarbonate resins (D)is, for example, from 1 to 50% by mass.

(Other Components)

The polycarbonate resin composition of the invention may contain variouskinds of additives such as an antioxidant, an ultraviolet absorber, alight stabilizer, and a flame retardant and various kinds of fillerssuch as glass, mica, talc, and rubber particles if necessary.

The polycarbonate resin composition of the invention may contain a resinother than the polycarbonate resin in a range in which the effect of theinvention is not impaired.

The polycarbonate resin composition of the invention contains a compound(also referred to as an exchange compound) produced as some or all ofthe side chain aryl esters in the constitutional unit (a1) isexchange-reacted with arbitrary one or more between a carbonyl bond andan ester bond in the polycarbonate resin (D). An apparatus for gaschromatography-mass spectrometry (GC-MS) equipped with a thermaldecomposition apparatus is used for the measurement of the proportion ofthese exchange compounds. The thermal decomposition apparatus may be anapparatus that can directly introduce the gas generated by thermaldecomposition to the GC-MS apparatus, for example, a micro vertical typesuch as the model PY-3030 manufactured by Frontier Laboratories Ltd. ora Curie point type such as the model JHP-5 manufactured by JapanAnalytical Industry Co., Ltd.

Mixed are 200 μg of the polycarbonate resin composition and 5 μL of a20% methanol solution of tetramethylammonium hydroxide (TMAH). Themixture is introduced into the thermal decomposition apparatus set at400° C. and the sample and TMAH are thermally decomposed through areaction. The gas generated by the reaction thermal decomposition isintroduced into the GC-MS apparatus, separated into each component bythe column in the apparatus for gas chromatography (GC), and analyzed bythe apparatus for mass spectrometry (MS), thereby obtaining a massspectrum. The measurement conditions of the GC-MS apparatus are, forexample, as follows.

Inlet temperature of GC apparatus: 280° C.

Separation column: DB-5 (length: 30 m×inner diameter: 0.25 mm×filmthickness: 0.25 μm)

Oven temperature of GC apparatus: 50° C. (kept for 2 minutes)→raising oftemperature at 10° C./min→320° C. (kept for 11 minutes)

Interface temperature of GC-MS apparatus: 280° C.

For example, in a case in which there is an exchange compound, a peakderived from the reaction thermal decomposition product of the exchangecompound is observed. Examples of the peak derived from the reactionthermal decomposition product of the exchange compound may include apeak that is derived from bisphenol A dimethyl ether represented by thefollowing Formula (3) at a retention time of 19.3 minutes and a peakthat is derived from methacrylate bisphenol A methyl ether representedby the following Formula (4) at a retention time of 22.1 minutes.

(Method of Manufacturing Polycarbonate Resin Composition)

The polycarbonate resin composition of the invention can be manufacturedby melt-kneading the polycarbonate resin (D), the (meth)acrylate resinmaterial of the invention, and, if necessary, other components.

Examples of the melt-kneading apparatus may include the Banbury mixer, akneader, a roll, a kneader ruder, a single screw extruder, a twin screwextruder, and a multi-screw extruder.

The polycarbonate resin composition of the invention can be manufacturedby melt-kneading the (meth)acrylate resin material at from 0.1 to 60parts by mass with respect to 100 parts by mass of the polycarbonateresin (D).

In addition, the polycarbonate resin composition of the invention can bemanufactured by melt-kneading the (meth)acrylate resin material at from1 to 300 parts by mass with respect to 100 parts by mass of thepolycarbonate resin (D) and, if necessary, other components, blendingthe polycarbonate resin (D) at from 1 to 400 parts by mass with thepolycarbonate resin composition thus obtained, and melt-kneading themixture.

(Composition of Polycarbonate Resin Composition)

The content of the (meth)acrylate resin material of the invention ispreferably from 0.1 to 60 parts by mass, more preferably from 10 to 50parts by mass, and still more preferably from 20 to 45 parts by masswith respect to 100 parts by mass of the polycarbonate resin (D). Themolded article has a superior surface hardness when the content of the(meth)acrylate resin material is 0.1 part by mass or more. The moldedarticle exhibits superior optical properties, namely, (transparency andthe like) when the content of the (meth)acrylate resin material is 60parts by mass or less.

The polycarbonate resin composition of the invention described abovecontains the (meth)acrylate resin material of the invention whichexhibits favorable compatibility with the polycarbonate resin (D), andit is thus possible to obtain a molded article having suppressed moldingdefects such as whitening in the case of molding the polycarbonate resincomposition of the invention.

In addition, in the polycarbonate resin composition of the invention,the (meth)acrylate resin material of the invention contains the(meth)acrylate polymer having the constitutional unit (a2) derived frommethyl methacrylate, and it is thus possible to obtain a molded articlehaving an excellent surface hardness in the case of molding thepolycarbonate resin composition of the invention.

In addition, in the polycarbonate resin composition of the invention,the (meth)acrylate resin material of the invention contains the(meth)acrylate polymer having the constitutional unit (a1) derived fromthe following Formula (1), and it is thus possible to obtain a moldedarticle exhibiting excellent optical properties, namely, transparency inthe case of molding the polycarbonate resin composition of theinvention.

Here, Ar is an aryl group, and the aromatic ring in Ar is directlybonded to the ester terminal in Formula (1).

<Molded Article>

The molded article of the invention can be obtained by molding thepolycarbonate resin composition of the invention.

Examples of the molding method may include a known method such as aninjection molding method, an extrusion molding method, or a compressionmolding method. As the molding method, an injection molding method andan extrusion molding method are preferable from the viewpoint of beingable to mold the polycarbonate resin composition into a desired shape.

The molded article of the invention described above is one that isobtained by molding the polycarbonate resin composition of theinvention, and it thus has an excellent surface hardness and suppressedmolding defects such as whitening.

In addition, the molded article of the invention described above is onethat is obtained by molding the polycarbonate resin composition of theinvention, and it thus exhibits excellent optical properties, namely,transparency.

EXAMPLES

Hereinafter, the invention will be described with reference to Examples.In Examples, the term “parts” represents “parts by mass”. The methods ofdetermining the proportion and mass average molecular weight of therespective constitutional units of the polymer and the method ofevaluating the molded article are as follows.

(Proportion of Constitutional Unit)

The proportions of the respective constitutional units of the polymerwere calculated from the charged amounts of the monomers.

(Mass Average Molecular Weight)

The elution curve of the polymer dissolved in tetrahydrofuran (THF) wasmeasured at a column temperature of 40° C. by gel permeationchromatography (GPC) using tetrahydrofuran as an eluent, and the massaverage molecular weight of the polymer was calculated based on thecalibration curve by standard polystyrene.

(Molding Defects)

The molding defects of a molded article were evaluated from the extentof whitening occurred on the molded article by visually observing amolded article having a thickness of 4 mm according to the followingcriteria.

A: Whitening is improved as compared with Comparative Example 1.

B: Whitening is caused to the same extent with Comparative Example 1.

C: Whitening is deteriorated as compared with Comparative Example 1.

(Haze of Whitened Site)

The haze of a region of 16 mm×12 mm including a place at which whiteningof the molded article was caused on a molded article having the shapeJIS K7162-1A was measured by using a haze meter NDH2000 (manufactured byNIPPON DENSHOKU INDUSTRIES Co., LTD.) in conformity with JIS K 7136.

(Pencil Hardness)

The pencil hardness of the surface of a molded article having athickness of 2 mm was measured in conformity with JIS K 5600-5-4.

(Transparency)

The haze of a molded article having a thickness of 2 mm was measured byusing a haze meter NDH2000 (manufactured by NIPPON DENSHOKU INDUSTRIESCo., LTD.) in conformity with JIS K 7136.

(Thermal Decomposition Measurement)

Mixed were 200 μg of a polycarbonate resin composition and 5 μL of a 20%methanol solution of tetramethylammonium hydroxide (TMAH). The mixturewas introduced into the thermal decomposition apparatus set at 400° C.and the sample and TMAH were thermally decomposed through a reaction.The gas generated by the reaction thermal decomposition was introducedinto a GC-MS apparatus (model PY-3030 manufactured by FrontierLaboratories Ltd.), separated into each component by the column in theapparatus for gas chromatography (GC), and analyzed by the apparatus formass spectrometry (MS), thereby obtaining a mass spectrum. Themeasurement conditions of the GC-MS apparatus were set to as follows.

Inlet temperature of GC apparatus: 280° C.

Separation column: DB-5 (length: 30 m×inner diameter: 0.25 mm×filmthickness: 0.25 μm)

Oven temperature of GC apparatus: 50° C. (kept for 2 minutes)→raising oftemperature at 10° C./min→320° C. (kept for 11 minutes)

Interface temperature of GC-MS apparatus: 280° C.

Carrier gas: Helium gas

Flow rate: 1 ml/min under constant flow condition

Example 1

Synthesis of Dispersant:

Into a 1200 L reaction vessel equipped with a stirrer, a cooling tube,and a thermometer, 61.6 parts of a 17% by mass aqueous solution ofpotassium hydroxide, 19.1 parts of methyl methacrylate (ACRYESTER Mmanufactured by MITSUBISHI RAYON CO., LTD.), and 19.3 parts of deionizedwater were charged. The solution in the reactor was stirred at roomtemperature, the exothermic peak thereof was confirmed, and the solutionwas then further stirred for 4 hours. Thereafter, the reaction mixturein the reactor was cooled to room temperature, thereby obtaining anaqueous solution of potassium methacrylate.

Into a 1050 L reaction vessel equipped with a stirrer, a cooling tube,and a thermometer, 900 parts of deionized water, 60 parts of sodium2-sulfoethyl methacrylate (ACRYESTER SEM-Na manufactured by MITSUBISHIRAYON CO., LTD., 42% by mass aqueous solution), 10 parts of an aqueoussolution of potassium methacrylate, and 12 parts of methyl methacrylate(ACRYESTER M manufactured by MITSUBISHI RAYON CO LTD.) were charged andstirred, the temperature was raised to 50° C. while purging the insideof the polymerization apparatus with nitrogen. Thereto, 0.08 part of2,2′-azobis(2-methylpropionamidine)dihydrochloride (V-50 manufactured byWako Pure Chemical Industries, Ltd.) was added as a polymerizationinitiator, and the temperature was further raised to 60° C. After thetemperature was raised, methyl methacrylate (ACRYESTER M manufactured byMITSUBISHI RAYON CO., LTD.) was continuously added thereto dropwise for75 minutes at a rate of 0.24 part/min. The reaction solution was kept at60° C. for 6 hours and then cooled to room temperature, therebyobtaining a dispersant having a solid content of 10% by mass of atransparent aqueous solution.

Synthesis of (Meth)acrylate Resin Material (β1):

Into a polymerization apparatus equipped with a stirrer, a cooling tube,and a thermometer, 200 parts of deionized water, 0.3 part of sodiumsulfate (Na2SO4), and 0.26 part of a dispersant (solid content: 10% bymass) were charged and stirred to obtain a uniform aqueous solution. Tothe aqueous solution in the polymerization apparatus, 20.3 parts ofphenyl methacrylate (ACRYESTER PH manufactured by MITSUBISHI RAYON CO.,LTD.) as a compound constituting the constitutional unit (a1), 79.7parts of methyl methacrylate (ACRYESTER M manufactured by MITSUBISHIRAYON CO., LTD.) as a compound constituting the constitutional unit(a2), 1.52 parts of methyl acrylate (manufactured by Wako Pure ChemicalIndustries, Ltd., special grade chemical) as a compound constituting theconstitutional unit (a3), 0.28 part of methacrylic acid (manufactured byMITSUBISHI RAYON CO., LTD.) as the acid (B) constituting theconstitutional unit (b1), 2 parts of 1-octanethiol (manufactured byTOKYO CHEMICAL INDUSTRY CO., LTD.) as a chain transfer agent, and 0.3part of 2,2-azobis-2-methylbutyronitrile (AMBN manufactured by NOFCORPORATION) as a polymerization initiator were further added, therebypreparing an aqueous dispersion. The inside of the polymerizationapparatus was thoroughly purged with nitrogen, the temperature of theaqueous dispersion was raised to 75° C. and kept for 3 hours, and thetemperature was raised to 85° C. and kept for 1.5 hours. The aqueousdispersion was cooled to 40° C., thereby obtaining an aqueous suspensionof a polymer. The aqueous suspension was filtered through a filtercloth, and the filtered product was washed with deionized water anddried at 75° C. for 18 hours, thereby obtaining a polymer. The polymerthus obtained was used as the (meth)acrylate resin material (β1). Theproportions and mass average molecular weights of the respectiveconstitutional units of the polymer constituting the (meth)acrylateresin material (β1) are presented in Table I.

TABLE 1 Constituent of (A1) or (A2) Amount of constitutional Amount ofunit with constitutional respect to 100 unit with Proportion of parts bymass respect to 100 constitutional unit in of (a1) + (a2) parts by mass100% by mass of (parts by of (a1) + (a2) (Meth) (a1) + (a2) (% by mass)mass) (parts by mass) acrylate (a1) (a2) (a3) (b1) resin Phenyl MethylMethyl Methacrylic Acrylic material methacrylate methacrylate acrylateacid acid Example  1 β1 20.3 79.7 1.52 0.28  2 β2 20.3 79.7 1.52 1.12  3β3 20.3 79.7 1.52 0.025  4 β4 20.3 79.7 1.32 0.1  5 β5 20.3 79.7 1.520.1  6 β6 15.2 84.8 1.52 0.1  7 β7 20.3 79.7 1.52 0.1  8 β8 20.3 79.71.52  9 β9 20.3 79.7 1.52 10 β10 15.2 84.6 1.52 11 α1 20.3 79.7 1.52 12α2 20.3 79.7 1.52 13 α3 20.3 79.7 1.52 14 α4 10.3 79.7 1.52 15 β15 20.379.7 1.52 0.1 16 α6 20.3 79.7 1.52 Comparative  1 γ1 20.3 79.7 1.52Example  2 γ2 0 100 1.52  3 γ3 0 100 1.52 0.1  4 γ4 0 100 1.52Constituent of (A1) Acid (B) or (A2) Amount of Nucleophilic Amount ofacid (B) agent (C) constitutional with Amount of unit with respect tonucleophilic respect to 100 100 parts agent (C) with parts by mass bymass of respect to of polymer (a1) + (a2) 100 parts by mass (A2) (parts(parts by of polymer (A1) by mass) mass) (parts by mass) Mass (c1) (B)(C) average PLACCEL Stearic Bisphenol molecular FM5 acid A BPX-55 weightExample  1 14000  2 14000  3 14000  4 14000  5 14000  6 14000  7 14000 8 0.51 14000  9 0.25 14000 10 0.51 14000 11 1 14000 12 5.1 14000 130.51 14000 14 1.1 14000 15 0.51 14000 16 4 (*) 14000 Comparative  114000 Example  2 14000  3 14000  4 1.1 14000 (*) indicates that additiontiming is simultaneous with polycarbonate resin (D)

Preparation of Resin Composition Containing Polycarbonate Resin (D) and(Meth)acrylate Resin Material (β1) and Evaluation of Molded ArticleFormed of Resin Composition:

In a polyethylene bag, 100 parts of the polycarbonate resin (D) (IUPILONS-2000F manufactured by Mitsubishi Engineering-Plastics Corporation) and25 parts of the (meth)acrylate resin material (β1) were put, and thesewere mixed by thoroughly shaking the polyethylene bag with hands. Themixture thus obtained was melt-kneaded at 280° C. by using a twin-screwextruder (PCM 35 manufactured by Ikegai Corporation), and the extrudedstrand was cut, thereby obtaining a pellet.

The pellet was molded at a molding temperature of 280° C. and a moldtemperature of 80° C. by using an injection molding machine (SE100DUmanufactured by Sumitomo Heavy Industries, Ltd.), thereby obtaining amolded article having a sheet shape and a thickness corresponding to therespective evaluations. The evaluation results are presented in Table 2.

TABLE 2 Polycarbonate resin (D) (parts by (Meth)acrylate resin material(parts by mass) mass) β1 β2 β3 β4 β5 β6 β7 β8 β9 β10 α1 α2 α3 α4 β15 α6γ1 Example  1 100 25  2 100 25  3-1 100 25  3-2 100 43  4-1 100 25  4-2100 43  5 100 25  6 100 25  7-1 100 25  7-2 100 43  8 100 25  9 100 2510 100 25 11 100 25 12 100 25 13 100 25 14 100 25 15 100 25 16 100 25Comparative  1-1 100 25 Example  1-2 100 43  2 100  3 100  4 100  5 100(Meth)acrylate Evaluation results resin material Haze of Haze of 2 mm(parts by mass) Molding whitened Pencil molded γ2 γ3 γ4 defects site (%)hardness article (%) Example  1 A 24 F 0.4  2 A 21 F 0.4  3-1 A 23 F 0.4 3-2 A 30 H 0.4  4-1 A 25 F 0.4  4-2 A 28 H 0.4  5 A 9 F 0.3  6 A 16 F0.1  7-1 A 20 F 0.4  7-2 A 30 H 0.4  8 A 17 F 0.4  9 A 18 F 0.4 10 A 23F 0.1 11 A 17 F 0.4 12 A 21 F 0.4 13 A 16 F 0.4 14 A 12 F 0.1 15 A 18 F0.1 16 A 19 F 0.4 Comparative  1-1 B 26 F 0.4 Example  1-2 B 32 H 0.1  225 C 88 F 0.1  3 25 C 86 F 0.4  4 25 C 89 F 0.4  5 A 1 2B  0.3

Examples 2 to 10

The (meth)acrylate resin materials (β2) to (β10) were obtained byconducting the same operation as in Example 1 except that the respectivecompositions were changed as described in Table 1. The proportions andmass average molecular weights of the respective constitutional unitsconstituting the (meth)acrylate resin materials (β2) to (β10) arepresented in Table 1.

Incidentally, acrylic acid (manufactured by Wako Pure ChemicalIndustries, Ltd., special grade chemical) was used in Example 7.

In Examples 8 to 10, an unsaturated fatty acid hydroxyalkylester-modified ε-caprolactone (PLACCEL FM5 manufactured by DAICELCORPORATION) was used as the nucleophilic agent (C) constituting theconstitutional unit (c1). The nucleophilic agent (C) was added to theaqueous dispersion before the inside of the polymerization apparatus waspurged with nitrogen.

Furthermore, the polycarbonate resin compositions of the invention wereprepared by using the polycarbonate resin (D) and the (meth)acrylateresin materials (β2) to (β10). The molded articles having a sheet shapeand a thickness corresponding to the respective evaluations wereobtained by conducting the same operation as in Example 1 except thatthe kind and amount of the (meth)acrylate resin materials blended werechanged as presented in Table 2. The evaluation results are presented inTable 2.

Examples 11 to 15

Polymers were obtained by conducting the same operation as in Example 1except that the respective compositions were changed as described inTable 1. The polymers thus obtained were further mixed with thenucleophilic agent (C) to obtain (meth)acrylate resin materials (α1) to(α4) and (β15). The proportions and mass average molecular weights ofthe respective constitutional units of the polymers constituting the(meth)acrylate resin materials (α1) to (α4) and (β15) and the amount ofthe nucleophilic agent (C) are presented in Table 1.

Incidentally, bisphenol A (manufactured by TOKYO CHEMICAL INDUSTRY CO.,LTD.) was used as the nucleophilic agent (C) in Examples 11, 12 and 15,and bisphenol A-propylene oxide adduct (product name: ADEKA POLYETHERBPX-55 manufactured by ADEKA CORPORATION) was used as the nucleophilicagent (C) in Examples 13 and 14.

Furthermore, the polycarbonate resin compositions of the invention wereprepared by using the polycarbonate resin (D) and the (meth)acrylateresin materials (α1) to (α4) and (β15). The molded articles having asheet shape and a thickness corresponding to the respective evaluationswere obtained by conducting the same operation as in Example 1 exceptthat the kind and amount of the (meth)acrylate resin materials blendedwere changed as presented in Table 2. The evaluation results arepresented in Table 2.

The polycarbonate resin composition obtained in Example 15 was subjectedto the thermal decomposition measurement as illustrated in FIG. 1. As aresult, peaks were confirmed at a retention time of 19.3 minutes and22.1 minutes in the mass spectrum. The samples having peaks at theseretention times of 19.3 minutes and 22.1 minutes were respectivelysubjected to mass spectrometry, as a result, the sample having aretention time of 19.3 minutes was attributed to a compound representedby Formula (3), and the sample having a retention time of 22.1 minuteswas attributed to a compound represented by Formula (4). The results onthe mass spectrometry are illustrated in FIGS. 2 and 3.

Example 16

A polymer was obtained by conducting the same operation as in Example 1except that a compound constituting the constitutional unit (b1) was notused. Furthermore, a polycarbonate resin composition was prepared in thesame manner as in Example 1 except that the polymer thus obtained,stearic acid (manufactured by Wako Pure Chemical Industries, Ltd.) asthe acid (B) of a constituent of the (meth)acrylate resin material (α6),and the polycarbonate resin (D) were simultaneously mixed at theproportions described in Table 2. A molded article having a sheet shapeand a thickness corresponding to the respective evaluations was obtainedby conducting the same operation as in Example 1. The proportions andmass average molecular weights of the constitutional units of thepolymer constituting the (meth)acrylate resin material (α6) and theamount of the acid (B) used are presented in Table 1. In addition, theevaluation results are presented in Table 2.

Comparative Examples 1 to 5

(Meth)acrylate resin materials (γ1) to (γ4) were obtained by conductingthe same operation as in Example 1 except that the respectivecompositions were changed as presented in Table 1. The proportions andmass average molecular weights of the constitutional units of the(meth)acrylate resin materials (γ1) to (y4) and the amounts of the acid(B) and nucleophilic agent (C) are presented in Table 1.

Incidentally, methacrylic acid (manufactured by MITSUBISHI RAYON CO.,LTD.) was used as the acid (B) constituting the constituent (b1) andbisphenol A (manufactured by TOKYO CHEMICAL INDUSTRY CO LTD.) was usedas the nucleophilic agent (C) in Comparative Example 3.

Furthermore, the polycarbonate resin compositions of the invention wereprepared by using the polycarbonate resin (D) and the (meth)acrylateresin materials (γ1) to (γ4). The molded articles having a sheet shapeand a thickness corresponding to the respective evaluations wereobtained by conducting the same operation as in Example 1 except thatthe kind and amount of the (meth)acrylate resin materials blended werechanged as presented in Table 2. The evaluation results are presented inTable 2.

Example 17

In a polyethylene bag, 100 parts by mass of the polycarbonate resin (D)and 100 parts by mass of the (meth)acrylate resin material (β7) were putand mixed by thoroughly shaking the polyethylene bag with hands. Themixture thus obtained was melt-kneaded at 280° C. by using a twin-screwextruder (PCM 35 manufactured by Ikegai Corporation), and the extrudedstrand was cut, thereby obtaining a pellet. To 100 parts by mass of thepellet thus obtained, 150 parts by mass of the polycarbonate resin (D)was further added, they were put in a polyethylene bag and mixed bythoroughly shaking the polyethylene bag with hands. The mixture thusobtained was melt-kneaded at 280° C. by using a twin-screw extruder, andthe extruded strand was cut, thereby obtaining a pellet. This is used asa masterbatch.

The pellet was molded at a molding temperature of 280° C. and a moldtemperature of 80° C. by using an injection molding machine, therebyobtaining a molded article having a sheet shape and a thicknesscorresponding to the respective evaluations. The evaluation results arepresented in Table 3.

Example 18

A molded article having a sheet shape and a thickness corresponding tothe respective evaluations was obtained by conducting the same operationas in Example 17 except that the (meth)acrylate resin material (β15) wasused instead of the (meth)acrylate resin material (β7). The evaluationresults are presented in Table 3.

TABLE 3 Example Example Blending (parts by mass) 17 18 Poly- Master-Poly- 100 100 carbonate batch carbonate resin resin (D) composition(Meth)acrylate 100 — resin material (β7) (Meth)acrylate — 100 resinmaterial (β15) Polycarbonate resin (D) 150 150 Evaluation Moldingdefects A A results Haze of whitened site (%) 23 21 Pencil hardness F FHaze of 2 mm molded article (%) 0.4 0.4

In Comparative Examples 1-1 and 1-2, the polymer (A1) was contained butthe acid (B) or the nucleophilic agent (C) was not contained, and theimprovement in molding defects of the molded articles was thus notconfirmed.

In Comparative Examples 2 to 4, a polymer other than the polymer (A1)and the polymer (A2) was used, and the extent of molding defects of themolded article was thus great.

In Comparative Example 5, the surface hardness enhancer was not used,and the pencil hardness was thus insufficient.

INDUSTRIAL APPLICABILITY

The molded article of the invention is useful as members (housing andthe like) of various kinds of devices (electrical devices, electronicdevices, office automation devices, and the like), optical recordingmedia, automobile parts (automobile headlamps, automobile interiormaterials, and the like), building members, and various kinds of sheets.

1. A (meth)acrylate resin material comprising: a polymer (A1) having aconstitutional unit (a1) derived from a compound represented by thefollowing Formula (1) and a constitutional unit (a2) derived from methylmethacrylate and at least one or more between an acid (B) and anucleophilic agent (C):

wherein, Ar is an aryl group, and an aromatic ring in Ar is directlybonded to an ester terminal in Formula (1).
 2. A (meth)acrylate resinmaterial comprising: a polymer (A2) having a constitutional unit (a1)derived from a compound represented by the following Formula (1), aconstitutional unit (a2) derived from methyl methacrylate, and at leastone or more between a constitutional unit (b1) derived from an acid (B)and a constitutional unit (c1) derived from a nucleophilic agent (C):

wherein, Ar is an aryl group, and an aromatic ring in Ar is directlybonded to an ester terminal in Formula (1).
 3. The (meth)acrylate resinmaterial according to claim 2, further comprising at least one or morebetween an acid (B) and a nucleophilic agent (C).
 4. The (meth)acrylateresin material according to claim 1, wherein the constitutional unit(a1) is at least one or more between a constitutional unit derived fromphenyl methacrylate and a constitutional unit derived from 2-naphthylmethacrylate.
 5. The (meth)acrylate resin material according to claim 1,wherein a proportion of the constitutional unit (a1) is from 5 to 50% bymass in 100% by mass of a sum of the constitutional unit (a1) and theconstitutional unit (a2).
 6. The (meth)acrylate resin material accordingto claim 1, wherein a proportion of the constitutional unit (a1) is from5 to 25% by mass in 100% by mass of a sum of the constitutional unit(a1) and the constitutional unit (a2).
 7. The (meth)acrylate resinmaterial according to claim 1, wherein a proportion of theconstitutional unit (a2) is from 50 to 95% by mass in 100% by mass of asum of the constitutional unit (a1) and the constitutional unit (a2). 8.The (meth)acrylate resin material according to claim 1, wherein the acid(B) is a compound having a carboxyl group.
 9. The (meth)acrylate resinmaterial according to claim 1, wherein the acid (B) is at least one ormore between methacrylic acid and acrylic acid.
 10. The (meth)acrylateresin material according to claim 1, wherein a content of the acid (B)is from 0.02 to 10 parts by mass with respect to 100 parts by mass of asum of the constitutional unit (a1) and the constitutional unit (a2).11. The (meth)acrylate resin material according to claim 2, wherein acontent of the constitutional unit (b1) or a total content of the acid(B) and the constitutional unit (b1) in a case of further comprising anacid (B) is from 0.02 to 10 parts by mass with respect to 100 parts bymass of a sum of the constitutional unit (a1) and the constitutionalunit (a2).
 12. The (meth)acrylate resin material according to claim 1,wherein the nucleophilic agent (C) is a compound having a hydroxylgroup.
 13. The (meth)acrylate resin material according to claim 1,wherein the nucleophilic agent (C) is a compound having a structurerepresented by the following Formula (2) in a molecule.


14. The (meth)acrylate resin material according to claim 1, wherein thenucleophilic agent (C) is a compound having a chemical structure toreact with a polycarbonate resin in a molecule.
 15. The (meth)acrylateresin material according to claim 1, wherein a content of thenucleophilic agent (C) is from 0.001 to 10 parts by mass with respect to100 parts by mass of the polymer (A1).
 16. The (meth)acrylate resinmaterial according to claim 2, wherein a content of the constitutionalunit (c1) or a total content of the nucleophilic agent (C) and theconstitutional unit (c1) in a case of further comprising a nucleophilicagent (C) is from 0.001 to 10 parts by mass with respect to 100 parts bymass of the polymer (A2).
 17. The (meth)acrylate resin materialaccording to claim 1, wherein a mass average molecular weight of thepolymer (A1) or the polymer (A2) is from 5000 to
 30000. 18. A surfacehardness enhancer comprising the (meth)acrylate resin material accordingto claim
 1. 19. A polycarbonate resin composition comprising: apolycarbonate resin (D); and the (meth)acrylate resin material accordingto claim
 1. 20. A molded article obtained by molding the polycarbonateresin composition according to claim
 19. 21. The surface hardnessenhancer according to claim 18, wherein a pencil hardness of a moldedarticle that is obtained by molding a polycarbonate resin compositioncontaining the surface hardness enhancer at 25 parts by mass withrespect to 100 parts by mass of a polycarbonate resin (D) having aviscosity average molecular weight of 16000 or more and 25000 or lessand has a thickness of 2 mm measured in conformity with JIS K 5600-5-4is F or higher.
 22. The surface hardness enhancer according to claim 18,wherein haze of a molded article that is obtained by molding apolycarbonate resin composition containing the surface hardness enhancerat 25 parts by mass with respect to 100 parts by mass of a polycarbonateresin (D) having a viscosity average molecular weight of 16000 or moreand 25000 or less and has a thickness of 2 mm measured in conformitywith JIS K 7136 is 0.5% or less.
 23. The surface hardness enhanceraccording to claim 18, wherein haze of a region of 16 mm×12 mm includinga place at which whitening of a molded article is caused in the moldedarticle that is obtained by molding a polycarbonate resin compositioncontaining the surface hardness enhancer at 25 parts by mass withrespect to 100 parts by mass of a polycarbonate resin (D) having aviscosity average molecular weight of 16000 or more and 25000 or lessand has a shape 1A described in JIS K7162 is 25% or less.
 24. A methodof manufacturing a polycarbonate resin composition, wherein apolycarbonate resin (D) is further blended at from 1 to 400 parts bymass with respect to 100 parts by mass of the polycarbonate resincomposition according to claim
 19. 25. A polycarbonate resin compositionhaving a peak at least at one or more retention times between 19.3minutes and 22.1 minutes in a mass spectrum obtained when 5 μL of a 20%methanol solution of tetramethylammonium hydroxide (TMAH) is added to200 μg of the polycarbonate resin composition, the polycarbonate resincomposition and TMAH are thermally decomposed through a reaction by athermal decomposition apparatus set at 400° C., and a gas thus generatedis separated.
 26. The polycarbonate resin composition according to claim25, comprising a polymer having a constitutional unit derived from atleast one or more between chemical structures represented by thefollowing Formula (3) and the following Formula (4).